You placed four radio buttons on a web form. You want the users to specify whether they are male or female and whether they are married or single. The code is as follows:
Male: <input type="radio" checked name="chk" value="male">
Female: <input type="radio" name="chk" value="female">
Married: <input type="radio" checked="checked" name="chk" value="married">
Single: <input type="radio" name="chk" value="single">
What is wrong with the above code?